Limit switch for valve-operating mechanism



June 7, 1927. 1,631,161

E. Aj RUSSELL ET A1.

LIMIT SWITCH FOR VALVE OPERATING MECHANISM Inv ums, l

E. A. RUSSELL ET AL LIMIT SWITCH FOR VALVE OPERATING IECHANISI Filed Sept. 5. 1925 2 Sheets-Sheet 2 June 7 1927. 1,631,161

et i) Patented June 7, 1927.

came 'STATES .PATENT OFFICE.

EDWARD A. RUSSELL, oF CHICAGO, AND BAUL n. PARKS, or' oAK PARK, IILLINoIsAssIGNoRs To VAPOR CAR HEATING COMPANY, INC., or CHICAGO, ILLINOIS, A COR- PORATION-OF NEW YORK.

LIMIT SWITCH FOR vALvE-ornATINe iv'ICHANIsr/I.

Application med september 5, i925. serial' No. 54,799.

This invention relates to improvements in an automatic valve-operating mechanism for a car-heating system, said mechanism including a new and improved limit-switch for automatically breaking the operating circuits to a `pair of valve operating motors, a'lfter eachmotor has functioned to move the valve to either an open orlcioselcl position.

In a car-heating system, such for example as shown in the patent to Russell LlllOOl, granted January 2, 1923, a control valve is provided having a rotary part which is to be swung at intervals from one position to another' to turn on or shut oli the steam supply to the 'car radiators, These movements ot the valve member are accomplished automatically by the thermally controlled mechanism whereby when the car atmospherebecomesheated to the desired temperature 'the valvel is moved by an electric metor or solenoid tto its closed position. llvlhen the temperature falls belowthe desired point, the valve is swung back byv another motor to open position, to aga'in admit heating medium te the radiators. A limit-switch is provided in the operating circuits for the motors, this yswitch being operated by the movement ot' the valve-operating lever to break the circuit to the v,operating motor after it has accomplished the desired valve movement. Thisinvention relates more particularly to a' new and improved switch for performing this function. f

@ne object ot the invention is to provide a switch oi this type comprising a pivoted contact member that is adapted to be quickly snapped 'from engagement with `one fixed Contact into engagement with another similar lixed Contact. The movement ot the valve-operating lever from one position to another serves to compress a spring, the spring being released as the lever'approaches he. end ot its movement, to quickly snap the movable contact member from one position to another, thus breaking the circuit to the motor, which has jnst moved the valve operating lever. The movable contact member iff.' elt in position to complete the circuit to the other motor, whereby the next valve-operating movement may be pei'- iiorme'd. Another object is to provide an improved electric terminal connector, for `ioining the ends ot the leads between the switch and the motors, and tor simultaneously holding the switch mechanism in position adjacent the motors.

Gther objects and advantages of this invention will be apparent from the following detailed description of one approved form ot' the mechanism involving the principles ot this invention'.

1n the accompanying' drawings:

Fig. l is a plan view of theassembled valve-operating mechanism, including the solenoids and the limit-switch.

Fig. 2 is a section, on a somewhat larger scale, taken substantially on the line 2 2 of Fig. l. A

F 3 is a section taken substantially on the line S-Sof Fig. 2.

Fig. l is an enlarged section through one or the terminal connectors, the view 1being taken substantially ontheI line 4 4 of Fig. l.

F 5 is a. section taken s'ubstantia-lly on the line 5 5 ol Fig. 4. p

Fig. 6 is a perspective view of one of the connector blocks.`

Fig. 7 is a perspective View i one of the slidable binding posts.

Fig. 8 is a diagrammatic view and wiring diagram, showing the' valve and its operating connections.

, Referring first to the diagram 'shown in Fig. 8, l is the control valve, comprising a i'b'tatable part 2 (shown in dotted lines), trom which projects an operating shaft 3, to which is attached the lever l for swinging the valve member from one position to another. Then the Va'lve is in the position shown, steam or other heating medium will flow in from the train pipethrough pipe 5, then through the valveand pipe 6 to the radiators troni which' it returns to the valve through pipes 7 and 8 and out through pipe 9'to the vapor-regulator. When lever l is swung overto a. corresponding position at the otherI side of the vertical, rotary meinber2 will be moved to'v cut 'off the flow ot all steam to the radiators, putting inlet pipe 5 in direct connection with outlet pipe S). A ll ol the above is more clearly disclosed in greater detail in the Russell patent referred to hereinabove.

llhe valve-operating lever 4 is moved from one position to the other by means ot a pair ot electric motors A and P), and C is the limit-switch Ytor automatically breaking the circuits to the two motors A and B, after each has functioned to move the valve. As here shown, the motors A and B are in the torm of a pair of solenoids, the coils 1() and 11 of which surrormd the ends ot a common core 12, which is centrally connected at 13 to one end o't operating lever 4. The two negative leads 14 and 15 from the thermally operated control mechanism are connected fith one end ot coils 10 and 11 respectively, and the other ends ot these coils are connected through wires 1G and 17 with a pair of liXed contact members 13 and 19 in limit switch C. The positive lead 2O from the control mechanism is connected to an oscillating member 21, carrying contacts 22 and 23 adapted to alternately engage with the fixed contacts 18 and 19. As already stated, with the parts in the position shown in Fig. 8, the valve 1 is open and steam is flowing to the radiators. When the car temperature has reached the desired maximum, the thermally operated control mechanism (not here shown but disclosed in the Russell patent hereinabove referred to), will close a circuit through solenoid A., the portion of this circuit here shown comprising positive lead 20, swinging contact member 21, contact 22, lined contact 13, wire 1G, coil l0, and negative lead v14. The energization of solenoid A. will draw in the core 12, thus throwing` lever 4 over to a corresponding position at the other side ot the vertical and closing valve 1. las lever 4 nears the end oi this movement it will, through delayed action mechanism in limit switch C, as hereinafter described, snap over the swinging member 21 to separate the contacts 18 and 22. thus breaking the circuit to motor A. At the same time, this portion of an operating circuit or motor B will be completed as iol.- lows: positive lead 20, swinging member 21, movable cont-act 23, fixed contact 19, wire 1T, coil 11, and negative lead 15. `When the car temperature has tallen below the desired point, the thermally operated control mechanism will complete a circuit through leads 2() and 15, whereby motor B will be energized to throw the valve back to the position shown in Fig. 8. nt the completion ot this movement, swinging member 21 will be snapped back to the position shown inl Fig. 8, breaking the circuit to operating motor B by separating the contacts 19 and 23.

Having now described in a general way the operation and purpose of this valveoperating mechanism and limit-switch, we will now reter to Figs. 1 to 7 for a. more detailed disclosure o'luthc mechanism. f lhe solenoids A and l are suitably supported within a casing 24, from one side ot which projects a tree end 25 oli operating` lever 4, by means of which the valve may be manually operated iii necessary. This end ci the operating lever may project over a suitably marked indicating plate 2G whereby the position ot' the valve may be easily'noted. will be seen that this arm ot the operatingl lever is engaged between a pair olf operating collars 13 .on the core 12 ot the solenoids, whereby the lever is automatically operated to swingY the valve shaft 3.

Blocks ot insulating material 2T and 23 are secured near the adjacent ends ot solenoid bodies A and B in any suitable manner, as by screws passing through these blocks into the casing ot the solenoids. Each block (ior example the bloc i 2T as shown in Figs. 4, and 6) has a pair of holes or passages 29 and 25) into which project the terminals 30 and 31 of the solenoid coil. rlhese passages 2) and 29"L partially intersect another pair ot passages 32 and 33 in the block, in which are slidably mounted the metallic binding posts 34 and 35. These posts have cut-away grooves or passages 36 and 37 adapted to register with the passages 29 and 29a and engage about the terminals 30 and 31. Preierably the passages 32 and 33 and the interl'itting posts 34 and 35 are of square or other irregular cross section to prevent. turning movement ot the posts in the passages and insure correct registration ot' grooves 3G and 37 with the passages 29 and 291. Binding` screws 33 and 39 engage in the upper ends oi the posts 34 and 35. Une end ot the lead wire 14 is engaged beneath the bindingv screw 39 and the screw is tightened. rl`his will draw up the post 35 to tightly clamp this post against the terminal 31 and insure a good electrical connection at this point, and will simultaneously draw the screw 3S) down against the lead 14 to make electrical.

contact at this point.

The limit switch C comprises a base plate 4() ot insulating material, on the back ot' which are mounted two metallic bracket-s 41 and 42 having projecting flanges 43 and 44 adapted to overlie the respective insulating` blocks 27 and 28. These [langes 43 and 44 are slotted to receive the binding screws 33, by means ot' which the switch C is secured to the insulating blocks. These brackets 41 and 42 also perjlorm the functions of the leads 16 and 17-o't' Fig. 8, so that it will be seen thatthe tightening` of screws 38 serves to simultaneously engage the posts with the coil terminals 30, to make electrical connections with the metallic brackets 41V and 442. and also te secure the limit switch C in assembled relation with the solenoids.

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the oppositeisidehof i'nsiilating base plete. 4o 'sie meent-ea, the @meer lea-S i5 mi 46, byjmeiis ,of screw-s. 47; mi, 48, .prof ject-.eig thrugii baise plete Alo ietebieekeie 41 and 4 2, whereby Vtlie pltes 45' and Zltar'e electrically, l connected with thezv 'rfe'spfective brackets., Plates ,4 5 carries iiXed contact member 18 and plate 46 'supports a similar fixed contact 1 9. A third coiitfa'ct-"plately is secured on the insuliting basejfl'() has a bracket extension 52 towhicli the positive lead 203is,'electrica'vlly connected. the other end `of plat'el is mounttfl afmetiillic loop 53, betweenthesides are pivoted the moving' parts of the \swit`ch. he movable Contact member 21 is 'of an'inverted T-shape, the arms of the'head :'i di the T carrying` the` contacts 22, and 23, adapted to engage1 respectively with the flied contacts 18 sind 19, The ,body portion of the is U shaped,'with the Aextremi ties ofjits legs 5T pivoted on fa pin 58 mounted in the sides ot' the loop liiopeitin'g. lever 59 is inte'rme'diatelyl Ypivotfed on another pin 6() mounted in Aloopl 53, there Ibfeiiilgiy tubiilar specei's 61 mounted about pin 60 between the sides of lever y59and tli'erespective' sides'of the loop. rI he longer arm otleve'r, 59 yis'engage@ bythe ferrea @ha e2 ef the' vaiveoperating lever'l. 'lliiscf'o'rkedA end` 62 of lever 1 isfo'rmed to hold a block of insulating material 6 3, held in place rivet- 64 vandnotcliedfat 65 to engage `aborittlie head of level: 5 9; The shorter'arm ofvlever "59? is 'slottedlettto permit swinging-movement ab'oiit Vthe lfixed pin y58, yand its eXtreme end is forledvat to. engage a pin 68 in vthee/rid of e link` 69. rIfhe other end of this link projects through an opening O in the head54'of the swinging Contact member. A Ycompres'sienspring is confined between the head 54 and a flange 72 on' link twill be seen that as the valve operating lever et is moved .rombne'side tothe Vother abeiit itspivot 3, it,will corresponding-ly swing the operating,lever- 59fabout its pivot 60, This movement of lever 5 9 'will swing the link G9 to bring it into substantial alignment with the lever, thus compressing the spring- 71. The parts will not pass beyond 4this position of alignment until the movement of lever 59 isnearly completed. ills soon as pin `68 is swung slightly beyond theline connecting pivot GOwith the aper-` ture'TO inhead 541, the spiing'71jvillsucldenly expend and snap the movable contact member over to its opposite position with contact 23 against contact 19, tlins breaking the cireuit through contacts 18 and 22. viously the same movements will takeplace in a reverse direction iipon the returnmovement of valve operating Al e ve r .l. It willbe noted that whilethe movements`-ofthe valve operating lever et may be comparatively slow and steady, `.the iiibvmeiit'bftlie iilovble contact 21 will be siifddten aiid will aka-bec@ hly after the en@ creeme iii'vements-have been practically completed. Obviously, theinot'or cit'ciiits as described connectionA with Fi'g` 8, willflew from ositive lead 2Q through the plate 51` andpthe mev'ab'le parts ef the switch tojthe'fiXed contact 18H or 19, with whichmovable contc inemberl21 is the-n engaged illiistratee in'the drawing, thecujrrent will flewufrom ylead 2 0 through plate 51, legs 57, lie'gid 54, 'Contact 2 2', contact 18, pleite 4 5, screw47, bracket 41 binding screw 38, binding post terminal 30,: coil 10, terminal 31, post 35,binding screw, and lead Wire 1 4 to the thermally operated controlling,` mechanism. y

'lt will be seen'that this new limitswiteh is compact .easily asse1nbled with the operating solenoids, and that; il miniiniim niui'ib'er ot' operating connections aie` in volved.. yThe new connect-or blocks, illustrated Figs. l to 7 inclusive, provide e conye1iient,ineans for mounting the limit switch on the solenoids, and at the same timeinsure tight electrical connections between the switch members and the coil-terminals. r lie movable parts of the limit-switclivmay be `enclose-d vin a removable 'casingf which snaps in, .placel on tlieninsulating Abase plate 10, and the entire valve-'operating assembly ymay be inclosed in e easing 24, herein-above referred to.

Ve claim 1. The combination with a valve compris-v inga rotary member, an opereting lever connected rwith the rotary member, and a pair ,of soleno'ids for alternately swinging the lever in one direction oi' thehother, of a limit switch comprising aninsulating' base, Athree separate electric terminal plates mounted oneaid base, a pairo'l' similar fixed contacts carried by two of the plates each o if thee plates also being,r electrically connected wit one terminal ot' one of the solenoids, an oscillatablemember p ivoted on the third plate and carrying;contact-members to alternately, engage with the fixed contacts as the member oscillated, a second operating' lever ,pivoted on the base and connected with the first mentioned operatingr lever, vand aspring mounted between portions of' the Second operating lever and oscillatable member Vwhereby `the spring will be stressed as the lever is moved to a position of' elignment therewith, and will thereafter operate to snap the member from one fixed contactto the other.

. 2. The combination Withavalve ycomprisL ing a rotary member, an operating lever connected with tlie 1otaiy member, and a pair of solenoids for alternatelyxswinging the lever in one direction or theothenof a ylimit switch comprising an insulating base,

three separate electric terminal plates mounted on said base, a pair of similar fixed contacts carried by two of the plates each of these plates also being electrically connected with one terminal of one of the solenoids, au oscillatable member pivoted on the third plate and carryingl contact members to alternately engage with the fixed contacts as the member is oscillated, a second operating lever pivoted ou the base and connected with the first mentioned operating lever, a link pivotally connected at one end with the second operating lever and slidably engaged at its other end with the free end of the oscillatable member, and a spring mounted. on the link and adapted to be compressed as the operating lever and link are swung to a position of alignment.

3. The combination with a valve coinprising a rotary member, an operating lever connected with the rotary member, and a pair of solenoids for alternately swinging- Vthe lever in one direction or the other, of a limit switch comprising an insulating base, three separate electric terminal plates mounted on the base, a pair of similar fixed contacts carried by two of the plates each of these plates also being electrically connected with one terminal of one of the solenoids, a T-shaped member having its leg portion pivoted on the third plate and carrying a pair of contacts, one on each arm of the' Thead, adapted to engage alternately with the fixed contacts, a second operating lever connected with the first operating lever and intermediately pivoted on the base with one end overlying t-he pivotcd leg of the member, and a compression spring mounted between this end of the lever and the head of the T whereby the spring will be compressed as the lever is swung into alignment therewith and will thereafter snap the member from a position against one fixed contact to a similar position against the other fixed contact.

4. In combination with a valve comprising a rotary member, an operating lever connected with the rotary member, and a pair of solenoids for alternately swinging the lever in one direction or the other, a pair of spaced fixed contacts each connected with a terminal of one of the solenoids, a swinging contact member adapted to engage alternately with the fixed contacts, one power lead for either solenoid being connected with this member, and connections comprising a spring between the operating lever and the swinging member whereby as the lever is moved by one solenoid to operate the valve the spring will be compressed and will snap the swinging contact member from one fixed contact to the other as the operating lever nears the limit of its movement, thus breaking the circuit through this solenoid.

5, in combination with a valve comprising a rotary member, an operating lever connected with the rotary member, and apair of solenoids for alternately swinging the lever in one direction or the other, a pair of spaced fixed contacts each connected with a terminal of one of the solenoids, a movable contact member adapted to alternately engage with the xed contacts, one power lead for either solenoid being connected with this movable member, and connections between the valve operating lever and the movable member comprising a spring which is compressed as the lever is moved by one solenoid to operate the valve, the spring snapping the movable member' from one fixed Contact to the other as the lever nears the limit of its movement, thus breaking the circuit through the operating solenoid.

6. In combination with a valve operating lever, a pair of solenoids for alternately swinging the lever' in one direction or the other, an insulating base plate, a pair of metallic supporting brackets mounted on one side of the base plate and secured one on each Solenoid, and each electrically connected with one terminal of the respective solenoid, a pair of fixed contact plates mounted on the opposite side of the plate, and electrically connected with the respective brackets, a third contact plate on the base, a movable contact member mounted on the plate and adapted to alternately engage with the fixed contacts,and connections between the movable contact member and the valveoperating lever.

7. The combination with a valve operating lever, and a pair of solenoids for alternately swinging the lever in Vone direction or the other, of a block of insulating material mounted on each solenoid, there being two intersecting passagesv in the block into one of which extends a terminal of the solenoid, a metallic post slidably fitting within the other passage andV having a cutaway portion to register with the first passage, a switch mechanism comprising a. pair of fixed contacts, a movable contact, the movable contact being operatively connected with the valve-operating lever, and a pair of supporting brackets electrically connected with the fixed contacts, and a binding screw engaging the exposed end of each post and adapted to'simultaneously .secure va bracket .to the block and draw the post into engagement with the solenoid terminal.

8. The combination with a valve operating lever, a solenoid for operating the lever in one direction, and means for operating the lever in the other direction, of a block of insulating material mounted on the solenoid the block having two pairs of intersecting passages, the terminals of the solenoid coil projecting into one passage of each pair, metallic posts slidably iitted in the other passages and having cutaway pertiens to register With the iirst passages, a switch mechanism Comprising a movable member operatively connected With the Valve-operating lever and a supporting bracket forming one terminal of the switch, and binding screws engaging the posts and drawing them into engagement with the solenoid terminals,

EDWARD A. RUSSELL. PAUL R. PARKS. 

